Method of molding



Aug. 24, 1943.

J. c. P. LEEMHUls 2,327,439

METHOD 0F MOLDING Filed Aug. 2e, 1958` s sheets-sheet 1 INVENTOR John nes Clyee/h/w/LS M T O R NEY 3 Sheets-Sheet 2 J. c. P. LEEMHuls METHOD OF MOLDING FiIed Aug. '26, 193s Aug. 24, 1943.

Il VIIIII ""IIIIIInI 1| ll I I All@ 24 1943 J..c. l?. LEEMHUls 2,327,43/9

METHOD 0f MOLDING Filed Aug. 26. 1958 3 Sheets-Sheet 5 sms@ Il Il N lll/7- Patented Aug. 24, 1943 UNITED STATES N PATENT oFFlcE METHOD F MOLDING Application August 2s, 193s, serial No. 226,92

4Claims.

This invention relates to the molding of material; and particularly concrete plates or slabs. Such plates are described and claimed in a prior application, llled on May 31, 1938,- under Serial Number 210,921, in the name of Johannes C. P. Ieemhuis and entitled: "Building materials and methods. This application is a continuation in part of said earlier illed application.

In the prior application, a system of joining the plates by the aid of pins passing through overlapped pillar sections formed integrally with the plates The present invention is particularly adapted to provide a mold in which the apertures for the pins may be accurately formed as by the aid of metal core pins.

In the process of molding, it is common to place the mold on a vibrating table while it is being illled, so as to cause the concrete mixture to iill accurately all of the mold spaces and to produce in general, a better molded article. Thereafter, it has been customary to place the iilled mold in a place where the article may acquire sulcient rigidity to permit stripping it from the mold. The quicker the stripping may occur, the less the number of molds need be for the same production.- It is another object of this invention to make it possible to strip the articles from the molds promptly upon completion of the molding operation.

This result is obtained by lining the mold surface with paper, such as multi-ply builders paper. Thls paper serves not only to support the newly molded plates so as to reduce slumping, but also prevents adhesion of the plate in the mold. A ccordingly it is another object o! this invention to utilize paper or the like as a mold lining.

The paper is preferably caused to adhere permanently to the plates, to form, as explained in the prior application, an insulation layer that is also impervious to moisture.

The plates, with the' adhering paper layer, are so placed that they form the innerl and outer portions 'of a building wall, the paper forming a layer substantially en- This invention possesses'many other advantages. and has other objects which may be made more easily apparent from a consideration of several embodiments of the invention.- For this purpose there vare vshown. ai'ew forms inthe drawings accompanying and forming part oi the f' present specification. These for-rhs,` which illus-.,`

trate the general principles of my invention, will now .be described in detail; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of my invention is best dened by the appended claims..y

Referring to the drawings:

Fig. 1 is a sectional view of a mold structure incorporating the invention, the structure being shown as having been lled` with plastic materia to form the cast article; i

Fig. 2 is a fragmentary sectional view, taken along plane 2-2 of Fig. 1;

Fig. 3 is a fragmentary sectional view, taken along the plane 3--3 of Fig. 1;

Fig. 4 is a side elevation of the mold structure illustrated in Fig. 1: v

Fig.- 5 is a view similar to Fig. 1, but showing the mold structure adapted for casting a slightly diierent form of concrete plate or slab Figs. 6 and 7 are respectively, fragmentary sectional views taken along planes 6-6 and 1-1 of Fig. 5, with the paper lining of the mold omitted;

Fig. 8 is a fragmentary top plan view taken along plane 8-8 of Fig. 5, and with the paper lining omitted;

Fig. 9 is a fragmentary sectionall view taken along plane S-S of Fig. 5;

, Figs.v 10 and 11 are views similar to Fig. 5, showing mold structures for casting other forms of plates;

Fig. 12 is a top plan view of the mold illus` trated in Fig. 1; and Y Fig. 13 is a. pictorial view, partly broken away, illustrating 4the plate that is cast by the aid of the mold structure illustrated'in Fig. 1.

The cast article l, in the form of a reinforced concrete plate structure, is shown more particularly in Fig. 13. It is formedvwith a series of spaced pillar sections 2, 3, 4 and 5. These pillar sections, as explained in the prior application I hereinabove referred to, are larranged to overlap pillar sections of similar plates and to'be anenored together by plins 'passing'through' apertures E and l, transverse to these sections'. Furthermore, if desired, the plate structure i may be reinforced -as by crossed wires or rods 8; 9, III, I I

In order to form a mold for this article; use is made of a metal moldbottom-member'ii. This mold bottom member may vl:efmacie"con` veniently from thin aluminum or the like. It is provided with appropriate downwardly extending recesses such as I4', for 'deiining mold spaces for the pillar sections 2, 3,.' t I.. bottom gur- As seen most clearly in Fig. 1, this bottom mold plate I3 is provided with integrallyv formed sides I4 and I5 defining the end surfaces of the recesses defining the pillar sections 2 and 5 respectively. The other sides required to complete the mold space, are shown as hinged to the depending edge iianges I6 and I1 of the bottom member I3 (Figs. 2 and 3). 'I'hus the hinged side I8 is shown as having a bottom rib I9 fastened to one element of a hinge structure 2|. 'Ihe other element 22 of the hinge structure is appropriately fastened, as by rivets 23, to the flange I6. As shown more clearly in Fig. 1, there may be several hinges spaced along the bottom edge of each side member. l

Similarly the opposite side member 24 is hinged by a plurality of hinge structures 25 to the depending flange I1 of the bottom plate I3. Accordingly' it is possible to open the mold structure by swinging the side member I8 in a counterclockwise direction as in Fig. 3; and by swinging side member 24 in a clockwise direction as viewed in Fig. 2.

Fastening means are provided for holding the side members I8 and 24 in the closed position illustrated. For this purpose use is made of a pair of through bolts 26 extending between the wings 21 formed integrally with the side walls I4 and I5 Y of the bottom plate I3. Each of the bolts 26 is' provided with a nut such as the wing nut 28 (Fig. 4). This Wing nut as well as the head 29 of each bolt 26 may be provided with collars or washers 30 and 3| engaged in recesses appropriately formed in the sides I 8 and 24.

In order to supplement the detachable fastening means 26 there are provided wing screws 32 (Fig. 3) placed in an intermediate position along each side wall I8 and 24 and passing through an appropriate aperture therein. These screws engage the threaded apertures in bosses 33 integral these core rods 34 and 35, lugs 31 are shown as depending below, and formed integral with, the bottom mold plate I3,l through which these rods 34 and 35 extend.

In the use of the mold as described in connection with the earlier filed application, the mold space is rst lined with insulation material such as builders paper 38. This may be two or three ply paper, adhered together as by tar or an asphaltic or other waterproof composition. This paper 38 substantially entirely covers the bot- 4tom of the mold and also projects along the sides I4 and I5. This paper lining is first placed within the mold prior to the insertion of the core rods 34 and 35.

' In order to provide a frame support by the aid of which the entire mold structure may be conveniently transported or otherwise handled, the

entire mold rests upon and is fastened to a rec-v tangular frame having the sides 39, 4l) (Figs. 3 and 4.)v andthe ends 4I and 42 (Figs. 1 and 2).

Aof the mold, as illustrated in Fig. 1.

plate I.

iiat surface resting upon the sides 39 and 4I, as illustrated more clearly in Figs. 2 and 3. Fastening screws such as 43 may be utilized -for attaching the frame 39, 40, 4I and 42 to the b0t tom of these lugs, and to the mold structure.

This frame extends somewhat beyond the sides There mi? also be provided standards 44 on the opposite ends 4I and 42. These standards provide a journal bearing 45 (Fig. 4)' forthe accommodation of pivot pins for facilitatingboth the transportation and the reversal of the mold in order to strip it from the cast article.

In using the mold structure the sides I8 and 24 are first attached by the aid of the bolts 26 and the screws 32, to the mold bottom I3. Then the paper 38 is disposed over the interior mold `surface. If desired, the reinforcing members l, l. IU, II and I2, which are fastened together to forma grid-like structure, may be placed inside of the mold. The core rods 3,4 and 35 may then be inserted. These rods, passing immediately above the reinforcing bars. I2 as shown in Fig. 1, ensure against material displacement of the reinforcements during the casting, process. The mold structure may now be disposed on a vibrating table in position for the concrete mixture to be poured into it to form the article I. In order to hold the assembled mold structure rmly to the table, use may be made of a pair of oppositely directed lugs 46 for accommodating a, clamping device.

Soon after this molding operation is completed, the mold may be inverted for stripping it from the article I. plate I because the newly molded plate is quite moist. There is, however, no material adhesion between the paper 38 and the mold surfaces so that no diiiiculty is experienced in this stripping act. Were it not for the paper, the the suction between the mold surface and the newly made concrete surface would be so great as to distort the freshly made concrete. By the aid of the intervening paper layer 38 this difficulty is en`- V tirely obviated. The paper also prevents the newly cast article from slumping.

The upper surface of the article I as illustrated in Fig. 1 is ,intended to form the-exposed .wall surface. before the article is removed from the mold: Il' desired, provision may be made to imbed sand within the exposed surface of th'e` plates, as by placing sand immediately upon completion ot the molding operation, upon the top surface of the gives a pleasing finish tothe exterior of the wall.

0f course, other types of finishes, as is well understood, might be used.

After the mold structure is reversed and the article I stripped therefrom upon the pallet, the

I pallet with the article loaded thereon may be placed into a curing chamber or kiln such as a steam chamber. The steaming process in a sultable kiln serves to produce a strong adhesion ol'- the paper 38 to the molded article I. This strong adhesion is probably due t the partial dissolution of the glucose matter; such glucose matter being incorporated within the paper during its manufacture. This glucose contacts the plastic ma.-

terial of the plate and serves as a bondbetween l The lugs 31 may be extended so as to provide a 75 the plate and the paper.

The paper 3B adheres to the l For that purpose it may be smoothed o!! This serves to prevent the concrete mix- In forming a complete biulding structure. plates dat wall surfaces. Other forms of the plates, v

however, are required to form interlocking corner members, all as fully described inthe above identied earlier :died application.

In the mold structure illustrated in Figs.,5, 6, 1, 8 and 9, the mold structures are used for casting a pair of plate sections which are intended to inter-fit at right angles to form a corner.

For this purpose the mold bottom plate 41 is shown as having an intermediate integral partition dii. This partition plate divides the mold structure into two mold spaces is and 50. The bottom of the mold space 4Q is formed by the bottom mold plate 5l of similar contour to the bottom member it of Fig. 1. It forms a recess di? to denne an edge pillar section. The recess 53 at the right hand end forms a rather wide space for a pillar section, and endingin a recess 54 for defining a projection. This projection is adapted to interiit in a corresponding recess formed in another plate to provide a rectangular corner structure.

In order to provide amold-waii for' the top surface ci the recess 5ft, use is made of a removable overhangihg mold member t5. This may be in the form of a hollow metallic trough-like structure shown in Fig. 8 as extending across the mold plate and supported on the hinged mold sides 56, as by the aid of a shoulder tl iFigs. 6 and 8) provided in the inner faces of the sides 5t. A limiting shoulder 5t (Fig. 5) is also provided on I the central partition dit to form a rest for the bottom edge of the structure This member iid is readily assembled and removed with respect to the mold. The supporting shoulders formed on the sides and the central partition dit ensure accurate positioning of this member. The space into which the concrete is to ow when the moid is being filled is thus accurately donned. The member remains in position on a pallet having the pillar forming recesses t5, 66 and 51. The bottom moldpiate t8 can be formed as an integral continuation of the mold plate 5I. In order to secure the desired coniiguration of the plate to be cast in mold space 50, a removable mold member 69 may be provided. This mold member 4ensures that the draw of the mold will be proper. It is shown to best advantage in Figs. 7 and 8. It may have its end edges accommodated ln grooves 10 formed on the inner surface of the hinged mold sides 56.

A core rod 1l is'` provided, to pass transversely through the recesses 66 and 61, and partly into the recess 65. As shown most clearly in Fig. 9, this core rod 1| isprovided with an annular groove 12 which is adapted to be engaged by one arm 13 of a. weighted lever 14. The weight 15 urges the arm 13 into locking position with respect to the annular groove 12. If it be desired to remove or replace the cord rod "il, the lever arm 13 may be depressed so as to move it out of Aengagement .with the annular groove 12.

So far as the supporting of the mold structure by the aid of a frame is concerned, this is entirely similar to that provided for -the mold structure illustrated 'in Figs. 1 to i inclusive.

En the mold structure illustrated in Fig. i0, the plate to be cast in the moldspace 18 is similar to that to be cast in the mold space te of Fig. ,5, except that it is extended to form a. longer plate section. Thus recesses lo and 1i corresponding to recesses t5 and 66 of Fig. 5; and the recess le corresponds to recess tl of Fig. 5. A

even after the mold. article is stripped from the 1 mold, so adequately to support the edge of the article against slumping.

The formation oicored apertures for the anchor pins is provided by the aid of several core rods These rods dit, however, while they extend completely through the recess iii, extend only partly into the recess 53. In order to ensure that the rods t@ will be accurately positioned with relation to the recess 53, so that it will extend to the desired amount only, into the recess, provisions are made for restraining the rod b9 from axial movement unless it be desired to remove or insert the rod 59.

Thus the rod et may be provided with an annular groove til adjacent the handle end li l. Into this groove a pivoted latch structure t2 is adapted to engage. It is urged to latching position by a weight. The details of this latching structure will be described in connection with the right hand mold 5t, as well as Fig. 9. l

Additional apertures are required to be formed in the plate molded in the space 49, which apertures are transverse to the space 54. For this purpose the bottom of the mold member 55 may be provided with a series of projections S3 contacting with a similar series of projections 64, shown as integral with the bottom plate 5|. These two sets of projections 63 and 64 cooperate to provide transverse cores. As many sets of these projections 63 and 64 may be provided as are required.

The right hand mold space is shown as recess t@ is also provided, symmetrical with the recess it. The end recess tl is similar to the other end recesses to form the end pillar section of the plate.

In. this case the core rod B2 can extendthrough all of the recesses 1.1, 13, B and di and .partly into the recess 1t. This core rod t2 may be held against axial displacement .by mechanism similar to that illustrated in Fig. 9. The recesses 65 and 16 are intended to form the edge portions dening a corner of the wall.

In other respects the mold structure illustrated in Fig. 10 is similar to the mold structures heretofore described.

In the form of the mold structure illustrated in Fig. 11, two short plates are intended to be cast, instead of one long plate as in the form of Fig. i. For this purpose there is a central integral partition t3 dividing the mold structure into the left hand mold space 8A and a right hand mold space 35. Since these mold spaces are symmetrical with respect to the partition s3 and sincev they are quite similar to that shown in Fig. 1, a detailed description is unnecessary. These mold spaces 84 and 85 simply omit the intermediate pillar section recesses and provide only the edge pillar section recesses, ysuch as 86 and 81. Common core rods 88, however, may be used to pass through all of the recesses in both of the mold spaces.

What is claimed is:

1. The process of molding a building unit from moist plastic cementitious material, said unit having a molded surface with projecting portions forming raised areas, which comprises covering the corresponding mold surface with a layer of pliant material, said layer being adapted to follow closely the congurations of the mold surface, placing the cementitious material in the mold, so as to leave one surface of the unitl exposed. dissurface is still plastic, and reversing the mold on a pallet `with the sanded surface in contact with the pallet. v

2. The process of molding an article from plastic material utilizing hydraulic cement, said article having a molded surface with projecting portions forming raised areas, which comprises covering the mold surfaces with a thin layer of glucose carrying material, said layer being adapted to follow closely the confiurations of the mold surface, pouring the plastic material into the mold, removing the molded article With the thin layer, from the mold, and subjecting the article and the layer to moist heat for bonding the layer to the article.

3. The process of molding an article from moist plastic cernentitious material, said article having a molded surface with projecting portions forming raised areas, which. comprises covering the corresponding mold surfaces with a pliant multilayer material having a composition that becomes adherent upon application of moist heat, said material being adapted to follow closely the congurations of the mold surface, pouring the plastic material in the moldthe pliant material adsorbing moisture from the plastic material and thereby to adhere to some extent to the molded article, removing the molded article with the pliant layer adhering thereto, and curing the article with the pliant layer by moist heat to cause a permanent adherence of the layer to the article.

4. The process of molding an article from a moist plastic cementitious material, which comprises: covering a mold surface with a layer of pliant material closely following the configuration of said surface and that does not adhere to said surface, said layer adhering to the article being molded by means of the moisture in the plastic material, and being freely removable from the mold, pouring the plastic material into the mold, removing the molded article from the mold with said layer adhering to the article, and steaming the article and the layer to bond the layer to the article.

JOHANNES C. P. LEEMHUIS. 

